1. Field of the Invention
The present invention generally relates to poultry feeds and, more particularly, to an improved poultry feed supplement.
2. Description of the Prior Art
Egg laying requires the ingestion and utilization by poultry of relatively large amounts of calcium, since egg shells largely comprise calcium in the form of calcium carbonate. Although poultry may ingest chips of calcium-bearing rock, for long-continued high-level egg production they require an additional source of calcium.
Various poultry feed supplements have been designed to provide poultry with the needed calcium and/or other nutrients. Conventional calcium-containing feed supplements utilize crushed limestone or crushed oyster shell, which is calcium carbonate, as the calcium source. See, for example, U.S. Pat. Nos. 2,403,010, 2,479,583, 2,668,749, 3,058,804 and 3,249,441. Such limestone is not assimilated very rapidly by the bird and such poultry feed supplements may fail to achieve the desired result of improved egg shell quality, particularly with older laying hens.
In many instances, despite the feeding of such a supplement, thin-walled low-shell-strength eggs are produced, resulting in high egg losses due to inadvertent shell crushing or fracture. It is also known that as egg production increases and/or the egg-laying population matures, calcium intake requirements rise and egg shell quality decreases. Older birds simply do not assimilate or metabolize calcium very efficiently.
Calcium has also been added with bone meal to poultry feed to improve broiler meat and egg color. See U.S. Pat. No. 2,940,856. Calcium phosphates have been coated with molasses to prevent dusting (see U.S. Pat. No. 4,252,831) and then fed to poultry. Lignosulfonates have also been used as feed supplements (see U.S. Pat. No. 2,905,558).
However, there remains a need to provide a more efficient calcium-containing poultry feed supplement which will improve the shell strength of eggs, even those of high production egg-laying strains and those of maturing poultry. The feed supplement should be inexpensive and simple to make and use from readily available ingredients.